Investigating the effects of silver nanoparticles in increasing the effectiveness of radiotherapy in breast cells pre-treated with metformin-loaded chitosan nanoparticles

Abstract

Breast cancer is the most common cancer among women, accounting for 11.7% of all cancer cases worldwide. This study aimed to enhance treatment efficacy by using silver nanoparticles as radiation sensitizers and chitosan as a nanocarrier to deliver metformin to breast cancer cells. Literature Review: Breast cancer is the fifth leading cause of cancer-related deaths. Recent research has focused on using radiation sensitizers to enhance tumor response to radiation therapy. Materials and Methods: Chitosan nanoparticles containing metformin and silver nanoparticles were synthesized using ionotropic gelation and chemical reduction methods, respectively. The physical properties of the nanoparticles, including size and surface charge, were examined using DLS and FE-SEM microscopy. Infrared spectroscopy was used to analyze the chemical bonding in the synthesized nanoparticles. The loading and release of metformin in the nanoparticles were measured. Cells were treated with chitosan nanoparticles containing metformin, followed by silver nanoparticles, and then exposed to X-ray irradiation at doses of 2, 4, and 8 Gy. Statistical analysis was performed using MTT assay, spheroid formation, DAPI staining, and FITC-labeled annexin V/PI flow cytometry. Results: The synthesized nanoparticles had an average diameter of 51.5 ± 9.4 nm for chitosan nanoparticles containing metformin and 3.02 ± 0.03 nm for silver nanoparticles. The toxicity of the nanoparticles was confirmed in MCF-7 cells and by DAPI staining. The highest increase in cell death was observed at an 8 Gy dose of irradiation in cells treated with both types of nanoparticles. The apoptosis rate in cells treated with chitosan nanoparticles containing metformin was 67.58%, compared to 42.30% for cells treated with free metformin.